I saw these on the currently watched on the top, they're getting quite popular, I'm 99.99% they used a hacking tool though, not to mention other than looking cool, it serves to real purpose, gives you no advantage over another player.

either they messed with the data on the disc (by modifying it and then burning it) or they are messing with memory addresses in the wii while the game is running....
I'd say there is a high probability this wont function correctly over WiFi play.